1. Field of the Invention
The present invention relates to an organic semiconductor compound and an organic thin film transistor using the same, and more particularly, to an organic semiconductor compound including thiazole, and an organic thin film transistor using the same which can be applied in a solution process and have an improved on/off ratio.
2. Description of the Related Art
Organic thin film transistors have several advantages which have made them a focus of active research and development. In particular, an organic thin film transistor can be fabricated in a simple process and at low cost, and can be easily applied to a flexible electronic circuit substrate that is resistant to breakage due to impact, and can be bent and folded.
In addition, compared to a conventional thin film transistor using amorphous silicon and polysilicon, an organic thin film transistor can be fabricated in a simple process and at low cost, and has excellent compatibility with substrates on which other electronic parts are mounted. It is for these reasons that organic thin film transistors have been widely researched in recent times.
However, for an organic thin film transistor to perform well, it should have a high on/off ratio and high charge mobility.
Also, an organic semiconductor forming the organic thin film transistor may be classified as small molecule semiconductor or polymer semiconductor depending on its molecular weight.
Generally, small molecule semiconductor can be easily purified to almost perfectly remove impurities and thereby obtain excellent electrical properties. But, it cannot be applied in a solution process such as spin coating and printing, and thus a thin film should be formed by vacuum deposition using an expensive vacuum device.
On the other hand, polymer semiconductor is difficult to thoroughly purify and its impurities cannot be perfectly removed. But, it has high thermal stability and can be applied in a solution process such spin coating and printing, and this it is preferable for low-cost processing and mass production.
Therefore, there is need to develop an organic semiconductor compound simultaneously having the advantages of both small molecule semiconductor and polymer semiconductor.